(1) Field of the Invention
The present invention generally appertains to improvements in fire hydrants, and more particularly relates to a new and novel guard arrangement for prevention of unauthorized turning of the hydrant operating stem and, in the instance of hydrants equipped with weather shields, to prevent said weather shields from being rotated or tampered with by unauthorized persons.
(2) State of the Art
The problem of unauthorized operation of fire hydrants is becoming more and more serious, particularly in larger cities. Problems caused by fire hydrant vandalism are loss of valuable treated water, street damage and street icing in winter, fire hydrants found to be inoperative when most needed, loss of water /pressure required to effectively fight a fire, and flooding of public and private property. To be totally acceptable to water and fire departments, a fire hydrant protective device must meet the following requirements:
A. The device must not prevent or delay authorized operation of the protected hydrant at any time. PA1 B. The device must be adaptable to all hydrant makes and models commonly in use because a fire protection system can be completely effective only when all hydrants in the system are protected. PA1 C. The device must provide protection for the hydrant weather shields on hydrants built with the weather shield feature. PA1 D. The protective device must be designed for quick, inexpensive field installation and removal without damage to, or alteration of, the internal mechanism of the hydrant. PA1 E. The device must be capable of withstanding a high degree of abuse. PA1 F. The device must be designed to prevent removal by unauthorized persons but allow for quick, easy removal by those authorized to make such removal for hydrant maintenance. PA1 G. The device must be available at a reasonable price.
Many attempts have been made to develop a device to protect against unauthorized operation and vandalism of fire hydrants by means of shielding the hydrant operating nut projecting above the hydrant bonnet, or by altering the internal mechanism of the hydrant. None provide protection of the hydrant weather shield, which can also be used to operate the hydrant.
For example, in U.S. Pat. Nos. 3,840,041 and 3,916,939, magnetic type arrangements of rather complicated design have been disclosed. Such devices require major internal modification of the hydrant, which can only be efficiently accomplished in a well equipped shop. They do not lend themselves to field installation. Since most of the hydrants to be protected are located in the field, moving them to the shop and back to the field again increases the cost of installation dramatically, and takes hydrants out of service for an unacceptable length of time. Also, since the hydrant internal mechanism is altered when the device is originally installed, expensive new internal parts must be purchased to put the hydrant back into operation in case the protective device is abandoned.
U.S. Pat. No. 2,118,233 reveals a patent wherein a protective collar encircles the hydrant operating nut with the collar being affixed to the hydrant bonnet by means of legs attached to the bonnet fixing bolts designed to hold the bonnet to the hydrant barrel. The attached legs are inadequate to hold the collar in place because the fixing bolts can easily be removed using common tools, permitting the complete removal of the device from the hydrant bonnet. Also, this device will not fit all makes of hydrants commonly in use.
In U.S. Pat. No. 4,390,038 a device is shown wherein a portion of the upper end of the hydrant operating stem, including the operating nut, is completely removed to make room for internal installation of a device which functions in response to a specially designed magnetic tool, which must be used in conjunction with a conventional hydrant operating wrench. The need for the fire fighter to use two tools simultaneously to operate the hydrant makes quick operation difficult and cumbersome. Installation of the device in the field would be next to impossible considering the major internal hydrant modifications required. Removal of the device leaves the hydrant without a functional operating stem which would need to be replaced at considerable expense if the hydrant is to be returned to its original operating condition. The device is designed to fit only one make of hydrant, leaving other hydrants in a fire fighting system unsecured.
In U.S. Pat. No. 3,453,655 a device is shown wherein a collar is built around the hydrant operating nut in such a manner that the operating nut can be engaged and turned by means of an ordinary 12-point deep socket wrench. The device involves a rather complicated modification of the internal hydrant mechanism to permit installation of a positive locking device. Field installation would be impractical making the system extremely expensive. Installation and/or removal of the device would take the hydrant out of service for an unacceptable length of time. Hydrants with weather shields cannot be protected by this device.
U.S. Pat. No. 4,369,807 is shown wherein a collar encircles the hydrant operating nut, said collar having an outward flange around the base where it meets the hydrant bonnet. An adapter designed with an inward flange is placed over the collar and lowered to contact the bonnet and interlock with the outward flange of the collar, said adapter then being welded to the hydrant bonnet leaving the collar free to rotate within the adapter. The device is simple and inexpensive, but there are weaknesses as well. The device cannot be easily removed for hydrant maintenance, and a skilled welder is required to do the installation.
U.S. Pat. No. 3,556,131 is shown wherein there is an externally mounted protective device providing limited access to the hydrant operating nut, the exposed portion of which is subject to engagement and operation by means of some common tools such as a chain wrench. Approximately half of the hydrants now in use are built with the weather shield feature. This device will not prevent operation of weather shield hydrants by means of a pipe wrench, or stilson wrench, applied to the exposed weather shield portion of the hydrant operating nut.
The device presently being offered for patent provides for quick, simple field installation and removal, without welding and without any mechanical alteration of the hydrant; complete protection of the hydrant operating nut and weather shield; it fits virtually all hydrants now in common use; and leaves the hydrant in its original working condition if the device is removed.
None of the foregoing patented devices meet all the requirements set out in (2) State of the Art. The device presently being offered for patent meets all of the requirements referred to in the above-mentioned paragraph.